Noninductive film-type resistors made by the silk screening of thick-film resistive material onto substrates are known in the art. For example, U.S. Pat. No. 3,858,147 teaches a serpentine pattern of film material silk screened onto a cylindrical substrate. As another example, reference is made to British Pat. No. 1,314,388, which teaches the silk screening of resistive material in a zigzag pattern onto a cylindrical substrate.
It is also known in the art to form serpentine resistors by the laser cutting of grooves in resistive material deposited by silk screening. This is often done, for example, relative to thick-film flat resistors, the films on which are fused before the laser cutting. U.S. Pat. No. 4,159,459 teaches a thin-film cylindrical resistor that is laser cut into a serpentine noninductive pattern.
In the laser cutting of resistive films on substrates, it is common practice to make two or more parallel and adjacent cuts in order to create a region where the removed resistive material, that is to say the gap between the remaining material, is wider than would be the case if there were only a single cut. Insofar as applicant is aware, such parallel cuts are of the same length.
High-voltage, noninductive, film-type resistors, both flat and cylindrical, are also well known in the art. However, such resistors are relatively large because of the necessity of maintaining gap widths adequate to prevent voltage breakdown, that is to say, bridging or short-circuiting of the gaps between adjacent undulations.